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Magnetic
flowmeters generate more revenues worldwide than any other type of flowmeter. In terms of units,
more differential pressure and variable area flowmeters are sold annually, but
magmeters' higher average selling price enables them to generate more revenues.
Magnetic flowmeters --
or magmeters, as they are often called -- have
also been around longer than any other new-technology flowmeter. The Tobinmeter Company first introduced magnetic flowmeters for commercial use in Holland in
1952 and Foxboro introduced them to the United States two years later. This puts their time of introduction well before that of other new technology flowmeters, including Coriolis (1977), ultrasonic (1963), and vortex (1969).
Consequently, magmeters have had more time to penetrate the markets in Europe, North America, and
Asia. Today more than 60 suppliers worldwide offer magmeters.
The newest edition of The
World Market for Magnetic Flowmeters, 6th Edition,
builds and expands on earlier editions in 2001, 2003, 2005, 2009, and 2015. We have updated and
broadened our segmentation based on extensive supplier input.
Why are magmeters so popular?
In addition to a large installed
base, magmeters have many advantages that help account for their role as the leading revenue-generating
flowmeter:
Willing to do the dirty
work. Most flowmeters do their best work in clean liquids or gases. Magnetic flowmeters, by contrast, thrive on dirty liquids.
They are used to measure the flow of conductive liquids and slurries, including pulp and paper slurries and black liquor.
Liners are the “secret
sauce” of magnetic flowmeters, enabling them to measure both very dirty and
very clean liquids. They can
measure the dirty and caustic liquids and slurries common to the pulp and paper and
wastewater industries, as well as the hygienic and sanitary liquids common to
the food & beverage and pharmaceutical industries.
Flexible. In addition to
liner flexibility, magmeters are available in a wide range of sizes from less than 1/8 inch to over 100 inches.
Furthermore, the development of insertion meters gives more options to end users who
want to measure liquids in large line sizes at lower costs.
Accurate and cost
effective: Magnetic flowmeters are highly accurate,
do not create pressure drop, and can be used for custody transfer applications. Magnetic flowmeters do not have moving parts, and provide a highly stable measurement.
Their initial purchase cost is medium to high, depending on size. While their price is generally higher than DP flowmeters, most are priced lower than equivalent Coriolis meters.
In addition, advanced diagnostics are making magmeters both more intelligent and more reliable.
Top industrial uses
Magmeters are widely used in the water
& wastewater industry. Thanks to new industry group standards that
include using magmeters for water utility measurement, magmeters are now
displacing positive
displacement and turbine meters in some residential and industrial
applications.
Magnetic flowmeters are also widely used in the
chemical, food & beverage, and pharmaceutical industries, due in part to the variety in
lining choices that enable them to measure a wide variety of liquids. Our data shows an increase in the use of
magmeters in these industries.
Magmeters are also making inroads
in oil & gas industry. Magmeters' main limitation is that they cannot measure hydrocarbons (which are nonconductive), and hence they
have not been widely used in the petroleum industry. However, they have come to be widely used in hydraulic
fracturing to measure the water injected into oil and gas wells for
"fracking" as well as the water flowing from them for capture,
disposal, or recycling.
Flow Research data shows an increase in both the percent of magnetic flowmeters used in the oil
& gas industry and the percent of magnetic flowmeters used for fracking applications.
New developments
While the magnetic flowmeter market is a mature and stable one,
some new product developments favor continued growth.
One recent development is the advent
and increasing popularity of two-wire magmeters. Four-wire meters have a dedicated power supply. Two-wire meters use the power available from the loop-power
supply, reducing wiring and installation costs. While two-wire meters still represent only a small percentage of the total magnetic flowmeters sold, their use
continues to grow.
Another important development is battery-operated and wireless magnetic
flowmeters. Battery operated meters make it possible to install magmeters in hard-to-reach places. And wireless meters can transmit a receivable signal where the use of wires is impractical. Both of these segments represent fast-growing areas of the magnetic flowmeter market.
Another recent development in product types is the trend toward
lower-cost, compact magnetic meters in the United States. Compact meters have traditionally outsold remote meters in Europe, while the reverse has been true in the United States.
While compact meters may be losing some ground to remote meters in Europe, they still dominate that market.
How they work -- AC vs. DC
Magnetic flowmeters use Faraday’s
law of electromagnetic induction. According to this principle, a voltage is generated in a conductive medium when it passes through a magnetic field.
This voltage is directly proportional to the density of the magnetic field, the length of the
conductor, and the velocity of the conductive medium. In Faraday’s law, these three values are
multiplied together, along with a constant, to yield the magnitude of the voltage.
Magnetic flowmeters use wire coils mounted onto or outside
a pipe. A voltage is then applied to these coils, generating a magnetic field inside the pipe. As the conductive liquid passes
through the pipe, a voltage is generated and detected by electrodes mounted on either
side of the pipe. The flowmeter uses this value to compute the flowrate.
When magnetic
flowmeters were first introduced, many had coils powered by continuous
alternating current (AC). These
devices had the disadvantage that they were subject to noise that interfered
with the proper reading of the meter. As
a result, they needed to be calibrated regularly against an onsite hydraulic
zero to maintain their accuracy.
Direct current
(DC) magmeters were developed to solve the problems from the noise
associated with AC meters. The DC meters are based on pulsed direct current.
When the current is turned on, a voltage is generated in the magnetic
flowmeter, showing the velocity of a flowing liquid.
When the current is turned off, any remaining voltage is assumed to be
due to noise. The meter computes
flow velocity by subtracting this extra remaining voltage.
While DC pulsed
technology was first introduced in 1974, it became popular in the 1980s, and its
popularity has grown since then. Many
pulsed
DC magmeters have the drawback, however, of lower
signal strength. This
gives AC meters an advantage for measuring some dirty liquids and slurries.
To compensate
for low signal strength, some DC meter suppliers developed “high strength”
DC meters. These high strength meters still use the pulsed on-off technology of
DC meters, but they have a higher coil current.
This makes them better able to handle high noise applications -- such as
slurries and dirty liquids -- than standard DC meters.
These high strength meters are growing rapidly in popularity.
Check out our articles
about magnetic flowmeters, events
occurring in the magnetic flowmeter market before 2010 and our previous
magnetic flowmeter studies:
The World Market for Magnetic Flowmeters, 5th Edition
Released in 2015
The World Market for Magnetic Flowmeters, 4th Edition
Released in 2009
The Global Market
for Magnetic Flowmeters, 3rd Edition
Provides historical perspective
The World Market
for Magnetic Flowmeters, 2nd Edition
Provides historical perspective
The World Market
for Magnetic Flowmeters, 1st Edition
Provides historical perspective
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